Lifting of broadly extending objects, and particularly large objects, with material handling systems may involve preliminary design steps to establish one or more pick point locations. The number of pick points and their locations may be selected to ensure that the stresses on the lifted object do not exceed allowable or design stresses on the object and may also be selected to ensure that no particular point would exceed the tensile capacity or design stress of the picking lines or slings, for example. In addition to these stress related considerations, the lifting design may give consideration to aligning the main lifting line with the center of gravity of the lifted object so as to maintain the object in a balanced condition during lifting of the object.
In some cases, insufficient time for a full design may be available or taking time to complete the design may delay the process. This may be particularly true during erection or decommissioning of a structure, for example. In the latter case, the particular size and shape of the parts and pieces that are removed and need to be handled may be unanticipated or unexpected. When lifting these parts and pieces, several attempts may often be made by slightly lifting the element to ensure it is balanced before fully lifting the element. Where imbalances are found, the part or piece may be set back down and a spreader beam may be manually adjusted to pick at different locations on the part or from different points along the spreader beam. This iterative process is slow, time consuming, and potentially dangerous.